NatureWorks a step closer to converting methane to lactic acid for biopolymers

US – NatureWorks is currently partnering US biotechnology company Calysta in a multi-year joint development program that aims to sequester and use methane, a potent greenhouse gas, as a feedstock for the former’s Ingeo biopolymers and intermediates.

The main goal of the R&D collaboration is to transform, via a fermentation process, renewable biomethane into lactic acid – which is the building block of polylactic acid (PLA) and biopolymers.

NatureWorks hopes to leverage Calysta’s Biological Gas-to-Chemicals platform for biological conversion of methane to high value chemicals to address its strategic interests in feedstock diversification and a structurally simplified, lower cost Ingeo production platform.

For NatureWorks, methane could be an additional feedstock several generations removed from the simple plant sugars used today in a lactic acid fermentation process at the NatureWorks Blair, Nebraska, Ingeo production facility.

The R&D has already seen some success: this June, a year after the joint development program was announced, Calysta demonstrated lab-scale production of lactic acid from methane, a major milestone in the project. Fundamental R&D should be completed in the next two to three years, enabling pilot production in three to five years.

A greenhouse gas 20 times more harmful than carbon dioxide, methane is generated by the natural decomposition of plant materials and is a component of natural gas. Biomethane refers specifically to renewably sourced methane produced from such activities as waste-water treatment, decomposition within landfills, farm wastes, and anaerobic digestion. If successful, the technology could directly produce lactic acid from any of these methane sources.

“If proven through this collaboration, methane to lactic acid conversion technology could be revolutionary, providing sustainable alternative feedstocks for Ingeo,” said NatureWorks Ken Williams, Program Leader for the Calysta-NatureWorks collaboration.

“When coupled with NatureWorks’ proven commercial process for lactic acid to Ingeo, the methane to lactic acid process would transform a harmful greenhouse gas into useful and in-demand consumer and industrial products. This disruptive platform could support high-value chemicals and liquid fuels.”

In October this year, The U.S. Energy Department’s Office of Energy Efficiency and Renewable Energy, Bioenergy Technologies Office announced a grant of up to US$2.5 million for this NatureWorks and Calysta research collaboration.